Clamping device for clamping a flexible covering on a cylinder of a printing machine

ABSTRACT

A clamping device for clamping a flexible packing ( 2, 3 ) of a cylinder ( 1 ) of a printing press, which cylinder has an axial channel ( 6 ) on a jacket surface, the clamping device includes a clamping body ( 10 ), which has a surface (S) that forms in the channel ( 6 ) with an opposite surface ( 4 ) a clamping gap for at least one end of the packing ( 2, 3 ) protruding through an opening ( 7 ) of the channel ( 6 ). A pressing device ( 13; 14; 10   a ) presses the clamping body ( 10 ) and the opposite surface ( 4 ) against each other with a clamping force (F). A mounting device ( 12; 14; 1, 8 ), which forms a support surface ( 9; 14′; 9 ′), touches the clamping body ( 10 ) and the clamping body ( 10 ) is supported on it. A center of gravity (SP) of the clamping body ( 10 ) can be moved, while the clamping gap is maintained, at right angles to an axis of rotation (D Z ) of the cylinder ( 1 ) in a first direction relative to the cylinder ( 1 ) and the support surface ( 9; 14′; 9 ′) and in a second direction that is not parallel to the first direction in relation to the cylinder ( 1 ).

FIELD OF THE INVENTION

The present invention pertains to a clamping device of a printing presscylinder, which is used to fasten a flexible packing of the cylinderclampingly on the cylinder.

BACKGROUND OF THE INVENTION

A clamping device as the one to which the present invention pertains isneeded especially for rubber blanket cylinders and/or printing cylindersof rotary printing presses to fasten a rubber blanket or a flexibleprinting form, which is tensioned on a jacket surface of such acylinder, on the cylinder while maintaining the tension. The cylindershave one or mostly a plurality of axial channels on their jacketsurface, in which channel or channels a clamping device each is formed.

EP 0 856 401 A2 discloses an axial channel, which has channel walls thatconverge obliquely at an acute angle in relation to one another up to achannel opening on the jacket surface of the printing cylinder. Aclamping body with lateral surfaces extending toward each other isarranged in the channel and tensioned in the direction of the channelopening, so that its two lateral surfaces are pressed against thechannel walls converging at the same angle. A clamping gap is formed forthe packing between one of the two channel walls and the lateralsurfaces of the clamping body facing it. The clamping gap is set bymeans of bearing bodies, which are arranged adjustably at right anglesto the clamping body.

Clamping devices that have clamping cams arranged pivotably in a channelof a printing cylinder are known from DE 195 09 561 A1 and DE 200 22 737U 1. The clamping cams are pivotable to and fro between a clampedposition and a released position.

The prior-art clamping devices are not yet optimal especially in respectto their handling.

U.S. Pat. No. 5,010,818 discloses a clamping device that comprises aplurality of cylindrical clamping bodies, each of which is directlysupported in an elastically nonrigid manner on a spring element in theradial direction of a printing cylinder. Even though the clamping bodiesare movable in two non-parallel directions at right angles to an axis ofrotation of the cylinder, partly due to the radial inward springexcursion of the spring elements and partly in the tangential directionof the cylinder, the movement in the tangential direction is associatedwith tilting and/or bending of the spring elements.

U.S. Pat. No. 5,123,353 discloses a clamping device with a clampingshaft, which is mounted movably on a mounting means of a pressing meansagainst a force of elasticity generated by the pressing means. Theclamping shaft has a regular cylindrical shape over part of its outercircumference and has a polygonal shape with either two or threeflattened areas opposite the regular cylindrical part. It lies on themounting means with its flattened areas. Depending on the number offlattened areas, it can assume two or three discrete angle of rotationpositions. It is shaped such on the regular cylindrical part of itscircumference that it does not form a clamping gap during the clampingof the ends of the packing. To clamp the ends of the packing, theclamping shaft is rotated by means of a tool into a predetermined angleof rotation position, in which it presses the ends of the packingagainst one of the gap ends of the cylinder channel, forming a clampinggap. Furthermore, two axial side walls of the channel, between which theclamping shaft is set movably, act as abutments for the clamping shaft.

Other clamping devices are known from DE 42 38 343 A1, U.S. Pat. No.2,900,904, U.S. Pat. No. 5,485,785, U.S. Pat. No. 5,123,353, DE 35 35138 A1, DE 101 08 745 C1, DE 44 15 624 A1, DE 26 20 427 B2, and U.S.Pat. No. 4,577,560.

SUMMARY OF THE INVENTION

One object of the present invention is to provide a clamping device forclamping a flexible packing of a cylinder of a printing press, by meansof which a cylinder packing is securely clamped and which is easy tohandle.

The present invention pertains to a clamping device of a cylinder of aprinting press, preferably a printing press for printing large newspapereditions. The cylinder has an axial channel on its jacket surface. Theclamping device comprises at least one clamping body, a mounting means,at which the at least one clamping body is supported, and a pressingmeans for the clamping body. The at least one clamping body has asurface that forms a clamping gap in the cylinder channel with anopposite surface for at least one end of at least one flexible packing,which said end protrudes through a channel opening. The opposite surfaceis preferably a channel wall that is formed by the cylinder itself or isconnected with the cylinder. However, the opposite surface may, inprinciple, also be movable in the channel in relation to the cylinder,e.g., it may itself likewise be rotatable, in order to facilitate theintroduction of a free end of the packing into the clamping gap. Thepressing means generates a clamping force, with which the at least oneclamping body and the opposite surface are pressed toward each other toform the clamping gap. The at least one clamping body and the oppositesurface are preferably pressed against each other already before the atleast one end of the packing is pulled in. However, the pressing forcemay, in principle, also be brought about only by the introduction of theend of the packing.

The at least one clamping body is mounted according to the presentinvention such that while the clamping gap is maintained, its center ofgravity can be moved at right angles to a longitudinal axis of thecylinder in two non-parallel directions in relation to the cylinder andalso in relation to the mounting means in one of the directions. The atleast one clamping body thus has two degrees of freedom of movement inthe plane of the cross section of the cylinder and permanently pressesthe opposite surface. The two directions of mobility of the center ofgravity of the clamping body and the axis of rotation of the cylinderpreferably form a right angle with each other. If the at least one endof the packing is pushed or pulled into the clamping gap, the at leastone clamping body is moved against the clamping force away from theopposite surface or is elastically compressed or it both moves away andis compressed in combination by the thickness of the end of the packing.During the displacement of its center of gravity, the at least oneclamping body is permanently supported on support surfaces and held inthis manner. The opposite surface which also forms the clamping gapforms one of the support surfaces. At least two more support surfacespoint at an angle to the opposite surface and also at an angle to eachother. The at least one clamping body is preferably supported andcentered by three support surfaces. One advantage of the arrangement ofthe at least one clamping body according to the present invention isthat no setting operations are needed for preparing the clamping gap.The at least one clamping body does not need to be moved first from areleased position into a clamped position, but it is always in theclamped position. The at least one end of a packing can be pushed orpulled into the clamped position. Two ends of the same packing or oneend each of two packings are preferably clamped in the clamping gap.

In a preferred embodiment, the mounting means is movable against a forceexerted by the pressing means on the at least one clamping body at rightangles to the axis of rotation of the cylinder. The mounting means canbe moved here in one of the two directions of mobility of the at leastone clamping body. The mounting means supports the at least one clampingbody in one of the two directions of its mobility and guides it in theother direction. The mounting means correspondingly forms a guide path,along which the at least one clamping body is guided, preferably byrolling and/or sliding on the guide path.

The surface of the at least one clamping body, which forms the clampinggap with the opposite surface, may be guided itself on the guide path.However, the clamping body is preferably guided on the guide path inanother manner, preferably by means of a meshing member that is rigidlyor optionally rotatably connected to the at least one clamping body. Thecircumference of the meshing member should press the opposite surface,and the meshing member should preferably press only the mounting means.It may project from the clamping body as a pin, i.e., as a bearingjournal. The meshing member is considered to belong to the clampingbody, because it follows the movements thereof in two directions.

The at least one clamping body is supported on support surfaces, whichare preferably formed in the channel of the cylinder. One of thesesupport surfaces is preferably formed by the mounting means, which isarranged movably in the channel in preferred embodiments. The othersupport surfaces may be formed especially by the cylinder itself and/orby a filler rigidly connected with the cylinder.

In a preferred first embodiment, the clamping body is mounted entirelymovably in two non-parallel directions. The mounting may be especially afloating mount, which is preferably formed by means of the movablyarranged mounting means. The at least one clamping body may be made inthis embodiment in one piece and homogeneously from a single material,e.g., steel or a comparably hard and heavy material.

In an alternative, second embodiment, the at least one clamping body iscentered between support surfaces, which are not movable in relation toone another. One of the support surfaces is again formed by the oppositesurface that participates in the formation of the clamping gap. The atleast two, preferably exactly two other support surfaces are preferablyformed directly by the cylinder or are rigidly connected with thecylinder. In this exemplary embodiment, the at least one clamping bodymay have a cylindrical jacket made of an elastically nonrigid material,which envelopes a hard core made of another material. Such a clampingbody may, in principle, also be formed entirely from the elasticallynonrigid material. However, a hard core made of a material with adensity that is higher than that of the material of the jacket ispreferred especially when the centrifugal force brought about by therotary movement of the cylinder shall be utilized to increase theclamping force. It can no longer be said in view of the secondembodiment that the at least one clamping body is arranged entirelymovably in the channel. However, at least its center of gravity is stillmovable in the two non-parallel directions. The clamping body forms thepressing means itself in these embodiments. If a hard core with anelastically nonrigid coating is jacketed, the coating is so thick thatit can perform an inward spring excursion when viewed over itscircumference by at least the thickness of an end of a packing andpreferably by at least the thickness of two ends of the packing.

The surface of the at least one clamping body, which participates in theformation of the clamping gap, is preferably shaped such that togetherwith the opposite surface, it forms an opening funnel in the plane ofthe cross section of the cylinder, which said opening funnel widens toan opening of the channel in order to facilitate the pushing in orpulling in of the at least one end of the packing.

The surface of the at least one clamping body, which participates in theformation of the clamping gap, is preferably shaped such that theclamping force acts only along a narrow, axially extending area even inthe case of an elastically nonrigid surface and/or opposite surface. Ahigh specific surface pressure can thus be advantageously attained inthe clamping gap.

The at least one clamping body may have a triangular or tetragonal crosssection or have another polygonal shape and participate in the formationof the clamping gap with one of its polygon edges. The polygon edges arepreferably slightly rounded without the polygonal character being lostas a result. The arrangement is, furthermore, preferably such that alinear clamping force and the opening funnel are formed.

However, the round shape of the surface of the at least one clampingbody, which surface participates in the formation of the clamping gap,is markedly preferred to a polygonal shape. It is preferably circular.

Even though the formation of the opening funnel, while the clamping gapor the clamping force acting in the clamping gap is maintained,cooperates especially advantageously with the mobility of the at leastone clamping body in the two non-parallel directions, it also offersadvantages even without such a mobility, which forms the subject of thisapplication. In an advantageous variant of the opening funnel, the atleast one clamping body is arranged rotatably around an axis of rotationand has the round surface that participates in the formation of theclamping gap, preferably around the axis of rotation.

The round surface of the clamping body is shaped such and it extends inthe circumferential direction around the axis of rotation of theclamping body to the extent that the clamping gap is maintained during arotary movement which is performed by the clamping body to clamp andrelease the packing. The clamping force remains at least essentially thesame, preferably in terms of magnitude and direction, during this rotarymovement, with unchanged thickness of the clamping gap. The clampingbody is in the clamped position in this case over the entire range ofangles of rotation over which its round surface participating in theformation of the clamping gap extends. This facilitates the introductionof a free end of the packing into the clamping gap. If the range ofangles of rotation over which extends the surface of the at least oneclamping body, which surface participates in the formation of theclamping gap, is large enough, the flexible packing may also betensioned in an advantageous variant by a corresponding rotary movementof the at least one clamping body. The round surface that forms theclamping gap with the clamping body especially preferably extends over360°. The clamping body is preferably rotatable by 360° around its axisof rotation.

In preferred embodiments, the round surface of the clamping body, whichparticipates in the formation of the clamping gap, is rotationallysymmetrical in relation to the axis of rotation of the clamping body.The clamping body is especially preferably designed as a regularcylinder, and the round surface is correspondingly a jacket surface ofthe regular cylinder. In the case of the rotationally symmetricaldesign, the at least one clamping body may basically also be a body ofrevolution deviating from the regular cylinder if a punctiform clampingforce is sufficient or even desirable in the clamping gap. In the caseof the rotationally symmetrical design, the at least one clamping bodyadvantageously forms the clamping gap in each angle of rotation positionover a full revolution, whereby operating errors are counteractedespecially reliably.

The pressing means is preferably a spring means, which presses the atleast one clamping body and its opposite surface against each other. Thepressing means is preferably arranged in the channel. In the design as aspring means, it comprises at least one spring element, which isarranged in the channel and is supported at the cylinder. If the atleast one clamping body is arranged rotatably, it is preferablyrotatable around its axis of rotation in relation to the pressing means.

A plurality of clamping bodies of the type described may be arranged inpreferred embodiments along a shaft or axis at axially spaced locationsfrom one another. The clamping bodies may be formed by the shaft or axisin one piece or fastened on a shaft or axis and preferably secured inthis design against rotation on the shaft and expediently againstdisplacement on the shaft or axis. A plurality of spring elements arepreferably arranged at spaced locations next one each other along theshaft or axis in order to uniformly press the plurality of clampingbodies against the opposite surface over the entire length of the shaft.If the clamping bodies are rotatable, rotary mounting on an axis is alsopossible as an alternative to the preferred formation of a shaft. Theshaft or axis sections between two adjacent clamping bodies preferablyform the above-mentioned pins, via which the clamping bodies aresupported on the mounting means.

A plurality of clamping bodies of the type described, which are notconnected to one another, are arranged axially next to one another inother preferred embodiments, and a clamping force is applied to each ofthem, as was described on the basis of a clamping body. Each of theclamping bodies may be mounted separately from each other of theclamping bodies. A plurality of clamping bodies, preferably two clampingbodies each, are preferably connected to one another and form a clampingbody group each, which is mounted separately, preferably by means ofpins, which connect the adjacent clamping bodies of one group to eachother.

The at least one clamping body and the opposite surface forming theclamping gap together with it are preferably arranged in relation to oneanother such that the clamping force has a direction component thatpoints in the direction of the centrifugal force which acts during therotary movement of the cylinder. It is preferred, furthermore, for theat least one clamping body as a whole or for at least the center ofgravity of the at least one clamping body to be movable in relation tothe axis of rotation of the cylinder. The component of the clampingforce caused by the centrifugal force at the maximum speed of thecylinder occurring during the operation is advantageously substantiallygreater than the clamping force component generated by the pressingmeans.

In the embodiments in which the at least one clamping body is arrangedrotatably in the channel, a blocking means may be provided, whichconnects the clamping body with the cylinder in a blocking engagementsuch that a reverse rotary movement of the clamping body is preventedfrom occurring. The blocking engagement can be released in order to makeit possible to pull the clamped end of the flexible packing out of theclamping gap. Such a blocking means may be formed especially by areleasable free-running mechanism, which does not hinder the rotarymovement of the clamping body in the clamping direction of rotation, butblocks the clamping body against a reverse rotary movement. The blockingmeans may also be formed by a friction brake that can be engaged andreleased. However, a blocking means is preferably not used, which ispossible especially when the centrifugal force supports the clamping.

Based on the design according to the present invention, the clampingbody is rotating in the clamping direction of rotation when the free endis pushed into the clamping gap and rolls with its round surface whichparticipates in the formation of the clamping gap on the free end of thepacking. Even though a rotating drive of the at least one clamping bodyis not necessary, a rotating drive shall not be ruled out. Because ofthe fact that the clamping gap is maintained over an angle of rotationrange, a rotatingly driven clamping body can be used to pull a free endof the flexible packing into the clamping gap and/or to push it out ofthe clamping gap. A rotating drive may also form at the same time theblocking means, e.g., by the self-locking of the rotating drive. Theself-locking may be achieved, e.g., by the use of a worm gear mechanism.

The present invention will be explained below on the basis of exemplaryembodiments. Features that become disclosed in the exemplary embodimentsrepresent variants of the subjects of the claims individually and in anycombination of features. The various features of novelty whichcharacterize the invention are pointed out with particularity in theclaims annexed to and forming a part of this disclosure. For a betterunderstanding of the invention, its operating advantages and specificobjects attained by its uses, reference is made to the accompanyingdrawings and descriptive matter in which preferred embodiments of theinvention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial sectional view showing a part of a printing cylindernear the jacket surface with an axial channel, in which a clampingdevice according to a first exemplary embodiment is formed;

FIG. 2 is a longitudinal partial sectional view of the clamping deviceaccording to FIG. 1;

FIG. 3 is a partial sectional view showing a part of a printing cylindernear the jacket surface with an axial channel, in which a clampingdevice according to a second exemplary embodiment is formed; and

FIG. 4 is a partial sectional view showing a part of a printing cylindernear the jacket surface with an axial channel, in which a clampingdevice according to a third exemplary embodiment is formed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings in particular, FIG. 1 shows a near thejacket-surface part of a printing cylinder 1 of a web-fed rotaryprinting press for the offset printing of large numbers of newspapercopies. The jacket surface of the printing cylinder 1 is spanned with aflexible packing. The flexible packing is a rubber blanket 2 in theexemplary embodiment, which is vulcanized or bonded to a flexible plate3. The printing cylinder 1 is correspondingly a rubber blanket cylinder.To span the flexible plate 3 with the rubber blanket 2 on the jacketsurface, the two free ends of the flexible plate 3 are pushed into achannel 6 and clampingly fastened in the channel 6 by means of aclamping device. The two clamped ends do not need to be the ends of thesame plate, and they are indeed not in many applications, e.g., when theprinting cylinder is a plate cylinder. The channel 6 extends axially,i.e., in parallel to an axis of rotation D_(Z) of the cylinder 1 on thejacket surface of the cylinder and forms a narrow channel opening 7directly on the jacket surface. The channel opening 7 is limited by twolimiting edges 1 v and 8 n, which are located opposite each otheraxially in parallel in the circumferential direction. If the cylinder 1is rotatingly driven in the direction of rotation D indicated by anarrow, the limiting edge 1 v forms the leading edge and the limitingedge 8 n forms the trailing edge of the channel opening 7. The channel 6widens in its cross section from the limiting edges 1 v and 8 n on bothsides of a radial R to the axis of rotation D_(Z) of the cylinder 1. Thechannel opening 7 and the adjoining channel walls 4 and 5 are axiallysymmetrical in cross section to the radial R. The ends of the flexibleplate 3, which are introduced into the channel 6, project beyond therubber blanket 2. The rubber blanket 2 itself is not introduced into thechannel 6, but it forms a narrow slot at the channel opening 7, or thetwo ends of the rubber blanket 2 abut each other above the channelopening 7.

A clamping device is formed in the channel 6. The clamping devicecomprises a plurality of clamping bodies 10, which are arranged atspaced locations axially next to each other on a shaft 11, which has anaxis of rotation D_(K). The clamping device comprises, furthermore, apressing means, which comprises in the exemplary embodiment a pluralityof spring elements 13 arranged at spaced locations next to one anotheralong the shaft 11 and a mounting means for the shaft 11. The mountingmeans is formed by a plurality of mounting pieces 12, namely, onemounting piece 12 each per spring element 13. The spring elements 13 acton the shaft 11 in the radial direction relative to the axis of rotationD_(Z) of the cylinder 1 via the mounting pieces 12. The clamping bodies10 are thus pressed by the pressing means in the radial plane ofsymmetry radially outwardly against the channel walls 4 and 5, whichextend on one side each of the radial planes of symmetry from the twolimiting edges Iv and 8 n. The two channel walls 4 and 5 are flat andextend axially. Because of the symmetry, they point to the radial planeof symmetry through which the radial R extends at the same slope angle.

The clamping bodies 10 form on their jacket surfaces S a clamping gapeach both with the channel wall 4 on the leading side of the channel 6and with the channel wall 5 on the trailing side of the channel 6. Thechannel walls 4 and 5 form the opposite surfaces for the jacket surfacesS of the clamping bodies 10 in the two clamping gaps. The two free endsof the flexible plate 3 are pushed into the clamping gap formed betweenthe jacket surface S and the leading channel wall 4 and are clampedbetween the channel wall 4 and the jacket surfaces S of the clampingbodies 10 with a linear clamping force F each. The introduction of theplate ends is facilitated by the funnel-shaped opening, which forms thesurface S with the opposite surface 4.

FIG. 2 shows a longitudinal view of the clamping device, wherein theclamping bodies 10, the shaft 11, which connects same or is formed inone piece with them, the mounting pieces 12 and the spring elements 13are shown in a view and the cylinder 1 is shown in a longitudinalsection of the radial plane of symmetry. The cross section A-A shown inFIG. 1 is marked in FIG. 2. The clamping bodies 10 are formed at equaldistances along the shaft 11 or are expediently fastened on thecontinuous shaft 11 secured against displacement and preferably securedagainst rotation. Slim shaft sections, which project from the clampingbodies 10 like pins and in which each of the spring elements 13 acts onthe shaft 11 via a mounting piece 12 each, are left between the clampingbodies 10. The spring elements 13 are accommodated in radial holes ofthe cylinder 1. The holes form at the same time radial guides for thespring elements 13 formed as compression springs each. The centrallongitudinal axes of the circular holes are radials R to the axis ofrotation D_(Z) of the cylinder 1, which extend in the radial plane ofsymmetry of the channel 6.

The shaft 11 is rotatable in the channel 6 around its axis of rotationD_(K), and the spring elements 13 press the shaft 11 via the mountingpieces 12 against the two channel walls 4 and 5. The channel walls 4 and5 and the mounting pieces 12 form in their cross section a three-pointbearing and as a whole a three-line bearing, by which the clampingbodies 10 are centered. The clamping bodies 10 can slide on both channelwalls 4 and 5 and also on the mounting pieces 12. The free rotatabilityof the shaft 11 is hindered, but not prevented, only by the frictionforces in the three contact points. The resulting friction force isdetermined by the material and the roughnesses of the contact surfacesand by the resulting force of elasticity G exerted by the springelements 13 on the shaft 11. The clamping force F acting in the clampinggap between the clamping bodies 10 and the channel wall 4 on the ends ofthe flexible plate 3 is correspondingly set by the judicious selectionof the material, the surface treatment and the spring force as desired.During the rotary movement, the clamping force F is increased comparedwith the state of rest by the component resulting from the centrifugalforce Z, which far exceeds the elasticity component G during theprinting operation.

The clamping bodies 10 are rotationally symmetrical to their axis ofrotation D_(K). Each of the clamping bodies 10 is a regular cylinder inthe exemplary embodiment.

In the initial state of the clamping device, in which the printingcylinder 1 is not spanned or at least the flexible packing 2, 3 is notyet clamped by means of the clamping device, the common axis of rotationD_(K) of the clamping bodies 10, i.e., the axis of rotation of the shaft11, extends in the radial symmetry plane of the channel 6. The springforce acting on the shaft 11 from the spring elements 13 points radiallyto the axis of rotation of the cylinder 1 through the axis of rotationD_(K) of the clamping bodies 10.

Based on the rotational symmetry of the clamping bodies 10, the balanceof forces between the resulting spring force G of the spring elements 13and the two resulting clamping forces F and P in the two clamping gapswith the channel walls 4 and 5 is the same in each angle of rotationposition of the bodies of revolution or clamping bodies 10.

if the two ends of the flexible plate 3 are pushed through the channelopening 7 in parallel to the leading channel wall 4 into the clampinggap between the clamping bodies 10 and the channel wall 4 in theabove-described initial state of the clamping device, the springelements 13 are slightly compressed, and the shaft 11 is moved at thesame time slightly to the side in the direction of the trailing channelwall 5 on the mounting pieces 12. The mounting pieces 12 form an axialsupport surface 9 each for the shaft 11, and the shaft 11 and theclamping bodies 10 can be displaced in parallel in relation to the axialsupport surface 9. The support surfaces 9 formed by the mounting pieces12 are flat in the exemplary embodiment and point at right angles, andin the example even exactly perpendicularly to the radial R and to theaxis of rotation D_(Z), as can be recognized in FIG. 1. The supportsurfaces 9 are guide paths for the transverse displacement of the shaft11. The slim sections of the shaft 11 remaining between the clampingbodies 10 form meshing members, which can slide and/or roll on thesupport surfaces 9. The support surfaces 9 as a whole and the channelwalls 4 and 5 form three support surfaces, which form angles with eachother and which enclose the shaft 11 between them in a triangularpattern and hold it centered. Because of the elastically nonrigidsupporting of the support surfaces 9 by the spring elements 13, theshaft 11 is mounted as a whole floatingly in the channel 6. The springelements 13 and the arrangement of the mounting pieces 12 on the springelements 13 are sufficiently rigid to prevent tilting movements of themounting pieces 12 during such a displacement. In the clamped stateshown in FIG. 1, in which the flexible packing 2, 3 is clamped in theclamping gap between the clamping bodies 10 and the channel wall 4 andthe shaft 11 was correspondingly displaced at right angles to the radialR, the axis of rotation D_(K) of the clamping bodies 10 extends to theradial symmetry plane of the channel 6 with a parallel offset through aparallel plane, which is represented in the cross section in FIG. 1 bythe straight line P which is parallel to the radial R.

Beginning from the initial state, the leading end of the flexible plate3, which end is bent at an acute angle, is pushed into the clamping gapbetween the clamping body 10 and the leading channel wall 4 andclampingly fastened as a result to fasten the flexible plate 3. Thetrailing end of the flexible plate 3 is subsequently introduced into thechannel 6 through the channel opening 7 via the trailing limiting edge 8n and likewise pushed into the clamping gap, which is formed between theclamping body 10 and the already clamped, leading end of the flexibleplate 3. The shaft 11 with the clamping bodies 10 seated on it rotatesaround its axis of rotation D_(K) during both pushing-in operations,rolling on the end of the flexible plate 3 that is being pushed in andslides on the mounting pieces 12 and on the trailing channel wall 5.Instead of pushing the two ends of the flexible plate 3 one afteranother into the clamping gap, both ends may also be pushedsimultaneously into the clamping gap, lying one on top of another. Dueto the mobility of the clamping bodies 10 and the shaft 11 in both theradial and tangential directions, each relative to the axis of rotationD_(Z) of the cylinder 1, no setting operations are necessary forclamping the plate ends. In the initial state and in the clamped state,in which latter state a distinction must be made between thenonoperative state of the cylinder and the states of the rotary movementof the cylinder, the clamping device adjusts itself to the thickness ofthe clamping gap, which thickness is predetermined by the plate ends.The forces acting on the clamping bodies 10 and on the shaft 11 formtriangles of forces, which are always congruent to each other, because,although the forces forming the triangle have different values in thedifferent states, their direction does not change. The fact that theclamping force F is the same in each angle of rotation position of theclamping bodies 10 at a given gap thickness because of the rotationalsymmetry of the clamping bodies 10 also contributes to thesimplification. In particular, it is not necessary to ensure that theclamping bodies 10 are in a certain angle of rotation position. Thedistinction between the clamped position and the released position ofthe clamping device is eliminated in this respect as well. The removalof the flexible plate 3 with the rubber blanket 2 is also facilitated.Manipulations on the clamping device itself are not necessary either forthe clamping or the removal. For removal, the clamped ends of theflexible plate 3 are pulled out of the clamping gap by means ofprior-art auxiliary devices, e.g., a suction device.

The shaft 11 may but does not have to be rotatingly driven. If the shaft11 is rotatingly driven by a motor or optionally via a crank handle, theends of the flexible plate 3 can also be pulled into the clamping gapand pushed out of the clamping gap by the rotary movement brought aboutby the motor or manually.

It can also be stated as an example regarding the geometry and thedimensions that the channel opening 7 has a gap width of 1 mm to 2 mmand typically 1.5 mm in the circumferential direction. The diameter ofthe clamping bodies 10 is between 20 mm and 30 mm. The two channel walls4 and 5 form an angle with each other that should be at least 60° and atmost 90°.

To facilitate the mounting of the clamping device, the channel 6 isformed in an axial recess of the cylinder 1 on the cylinder jacketsurface that is larger than the channel 6. A filler 8 is inserted intothe recess in an accurately fitting manner. The filler 8 forms thechannel walls, especially the channel wall 5, on one side of the radialsymmetry plane of the channel 6. The channel walls on the other side ofthe radial symmetry plane are formed directly by the cylinder 1; this isespecially the leading channel wall 4 that participates in the formationof the clamping gap in the exemplary embodiment. The filler 8 forms,furthermore, a section of the cylinder jacket surface, which is short inthe circumferential direction, including the trailing limiting edge 8 nof the channel opening 7. The recess in the cylinder 1 has asufficiently great extension in the circumferential direction to makepossible the insertion of the pressing means and of the shaft 11 formingthe clamping body 10. The filler 8 secures the entire arrangement in thechannel 6. One peculiarity that shall be mentioned in connection withthe filler is the simplified formation of the recess and of the filler8. The recess is shaped, e.g., milled, as a straight rectangular groove.One of the two parallel side walls of the rectangular groove forms theopposite surface 4. The filler 8 is also characterized by rectangularedges, which can be shaped in a simple manner. In particular, an inneredge is formed, which is open in two directions and in which two sidewalls of the filler 8 converge at right angles. Of these two side walls,the one pointing radially inwardly forms the opposite surface 5. Thefiller 8 is fastened to the cylinder 1 by means of screws via the other,radially outwardly pointing side wall of the inner edge. Anon-perforated, smooth jacket surface of the cylinder 1 can thus also beobtained in the area of the filler 8.

When the clamping body 10 will hereinafter be described only as oneclamping body 10, that description shall correspondingly apply toembodiments with a plurality of clamping bodies 10 as well.

FIG. 3 shows a clamping device according to a second exemplaryembodiment. The parts of the clamping device that have the samefunctions as the corresponding parts of the first exemplary embodimentare designated by the same reference numbers. The clamping deviceaccording to the second exemplary embodiment also comprises acylindrical clamping body 10, which can be arranged with a plurality ofsuch clamping bodies 10 on a shaft or rotatably on an axis, or it formsa shaft of a uniform thickness. If a plurality of packings 2, 3 arespanned next to each other in the axial direction around the cylinder 1,a plurality of separate clamping bodies 10 may also be arranged axiallynext to each other in the channel 6, in which case the axial lengths ofthe clamping bodies 10 correspond each to the lengths of the packings 2,3 measured in the axial direction. A plurality of clamping bodies 10,which are identical in their cross sections and preferably also in theirlengths, are arranged in likewise preferred embodiments in a number thatis greater than the number of packings 2, 3 spanned next to each otheraround the cylinder 1.

The clamping body 10 or the plurality of clamping bodies 10 according tothe second exemplary embodiment is/are of a regular cylindrical shape.The clamping body 10 or the plurality of clamping bodies 10consists/consist of a preferably hard material, e.g., steel or amaterial with a comparably high specific gravity. The clamping body 10is supported on two elastic bearing bodies 14. The bearing bodies 14 arein turn supported on the support surface 9′, and one bearing body 14 isadditionally supported on the channel wall forming the opposite surface4, and the other bearing body 14 is supported on the channel wallforming the opposite surface 5 by the bearing bodies 14 being arrangedin the particular inner edge of the channel 6 being formed.

Before the introduction of the ends of the packing 2, 3, the bearingbodies 14 press the clamping body 10 with a force of elasticity againstthe opposite surface 4 and against the opposite surface 5. The bearingbodies 14 can perform an inward spring excursion in their combination tothe extent that the two ends of the packing 2, 3 can be introduced intothe clamping gap. During the elastic yielding of the bearing bodies 14,the clamping body 10 is displaced away from the opposite surface 4,preferably at right angles to the opposite surface 4, against therestoring force of elasticity of the bearing body 14 arranged oppositethe opposite surface 4. If the clamping gap is formed with the oppositesurface 5, corresponding statements can be made concerning the bearingbody 14 arranged opposite the opposite surface 5. Furthermore, theclamping body 10 is rotatable around its own axis of rotation D_(K). Therotatability is not absolutely necessary, but it does facilitate thepulling in and the removal of the packing 2, 3 with the cylinder notmoving.

The bearing bodies 14 according to the second exemplary embodiment areelastic in their material and have a Shore hardness of preferably 70Shore±10 Shore. They are solid cylindrical. However, a hollowcylindrical design would be conceivable as well. Instead of an elasticmaterial, a hard material, e.g., spring steel, could also form thebearing bodies 14 in the case of the hollow cylindrical design, butthese bearing bodies 14 would have to be elastic due to their shape inthis case. In a shape elastic design, the bearing bodies may be formed,in particular, by a spiral spring each, which are inserted loosely intothe inner edges of the channel 6, like the bearing bodies 14 accordingto the second exemplary embodiment. The opposite surfaces 4 and 5 form afour-point support for the clamping body 10 with the two bearing bodies14.

FIG. 4 shows a clamping device according to a third exemplaryembodiment. The reference numbers of the first exemplary embodiment arealso used in the third exemplary embodiment if the parts of the clampingdevice in question have the same functions as do corresponding partsaccording to the first exemplary embodiment. Unless indicated otherwisein connection with the third exemplary embodiment, the statements madein connection with the first exemplary embodiment also apply to thethird exemplary embodiment.

The clamping device according to the third exemplary embodiment likewisecomprises clamping bodies 10, which may be integrated in a shaft orarranged individually and at axially spaced locations from one anotherin the channel 6, as in the first exemplary embodiment. A continuousshaft, which has the same diameter over its entire length, may also forma single clamping body 10, which is also possible in the first exemplaryembodiment and, as was mentioned, in the second exemplary embodiment aswell. However, contrary to the first exemplary embodiment and also tothe second exemplary embodiment, the clamping bodies 10 are notdisplaced as a whole when the plate ends are clamped, because theclamping bodies 10 or the clamping body 10 are/is centered and heldbetween support surfaces 4, 5 and 9′, none of which is movable inrelation to the cylinder 1. The opposite surfaces 4 and 5 correspond tothose according to the first exemplary embodiment. The opposite surface9′ is formed by the filler 8. These support surfaces 4, 5 and 9′ cannotchange their positions relative to each other. It shall be assumed belowas an example that the clamping device has a plurality of clampingbodies 10, which are not connected to one another.

To make it possible to introduce the plate ends into the clamping gap,which is formed by each of the clamping bodies 10 with the oppositesurface 4, each of the clamping bodies 10 is elastically nonrigid on thesurface S that participates in the formation of the clamping gap. Theclamping bodies 10 may consist entirely of a corresponding material.Each of the clamping bodies 10 is, however, designed as a composite bodyin the exemplary embodiment, which comprises a jacket 10 a made of anelastically nonrigid material and a core 10 i, which envelopes thejacket 10 a concentrically to the center of gravity axis SP at a closelyspaced location therefrom. The material of the core 10 i is hard andadvantageously has a greater density than the elastically nonrigidmaterial of the jacket 10 a, so that the density of the clamping bodies10 can be increased compared with an entirely elastic design. Thecomponent of the clamping force originating from the centrifugal forcecan be increased as a result. The elastically nonrigid material of thejacket 10 a and the geometry of the channel 6 as well as the diameter ofthe clamping bodies 10 measured on the surface S shall be such anddimensioned such that the clamping bodies 10 can rotate around thecenter of the gravity axis SP when the plate ends are introduced intothe clamping gap. However, this is not absolutely necessary.

Even though it is already clearly apparent from FIGS. 1 and 4, it shallalso be mentioned in connection with the clamping devices according tothe first and third exemplary embodiments that they form the sameclamping gap with both the opposite surface 4 and the opposite surface 5arranged opposite. The plate ends of a flexible packing 2, 3 or of twodifferent flexible packings 2, 3 can therefore be introduced into theclamping gap formed with the opposite surface 4 or into the clamping gapformed with the opposite surface 5 as desired and clamped there. Theaction of the clamping device is independent from the direction ofrotation of the cylinder 1.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

1. A clamping device for clamping a flexible packing of a cylinder of aprinting press, which said cylinder has an axial channel on its jacketsurface, the clamping device comprising: a clamping body, which has asurface that forms a clamping gap in the channel with an oppositesurface for at least one end of the packing protruding through anopening of the channel; a pressing means, which presses the clampingbody and the opposite surface onto each other with a pressing force; anda mounting means, which forms a support surface, which touches theclamping body and on which the clamping body is supported; wherein thecenter of gravity of the clamping body can be moved, while maintainingthe clamping gap, at right angles to a axis of rotation of the cylinderin a first direction relative to the cylinder and the support surfaceand in a second direction that is not parallel to the first directionrelative to the cylinder.
 2. A clamping device in accordance with claim1, wherein the mounting means can be moved in the second directionrelative to the cylinder and it guides the clamping body in and againstthe first direction.
 3. A clamping device in accordance with claim 1wherein the mounting means guides the clamping body at right angles tothe axis of rotation of the cylinder.
 4. A clamping device in accordancewith claim 1, wherein at least three said support surfaces, which centerthe clamping body and mount it movably at right angles to the axis ofrotation of the cylinder, are formed in the channel.
 5. A clampingdevice in accordance with claim 1, wherein the clamping body is arrangedrotatably in the channel, and a surface of the clamping body thattouches the support surface is round, so that the at least one clampingbody can roll and/or slide on the support surface.
 6. A clamping devicein accordance with claim 1 wherein the surface of the clamping bodyforming the clamping gap is round.
 7. A clamping device in accordancewith claim 6, wherein the clamping body is mounted rotatably around aaxis of rotation and that the round surface is shaped such and has suchan extension in the circumferential direction around the axis ofrotation of the clamping body that the clamping gap is maintained duringa rotary movement of the clamping body around the axis of rotation.
 8. Aclamping device in accordance with claim 6, wherein the round surface ofthe clamping body is rotationally symmetrical relative to a axis ofrotation of the clamping body.
 9. A clamping device in accordance withclaim 1, wherein the clamping body is rotatable relative to the pressingmeans around a axis of rotation.
 10. A clamping device in accordancewith claim 1, wherein the pressing means is a spring means, which actson the clamping body with a force of elasticity.
 11. A clamping devicein accordance with claim 1, wherein the pressing means exerts a force ofelasticity on the clamping body, which said force points radially towardthe axis of rotation of the cylinder or has at least a radial component.12. A clamping device in accordance with claim 1, wherein the pressingmeans comprises at least one said cylindrical bearing body, which isarranged lying in the channel, is elastic in its material and/or elasticdue to its shape and forms the support surface.
 13. A clamping device inaccordance with claim 12, wherein the bearing body is arranged in ainner edge, which is formed in the channel and opens toward the oppositesurface forming the clamping gap.
 14. A clamping device in accordancewith claim 12, wherein an additional bearing body is arranged in thechannel in a inner edge of the channel, which said inner edge openstoward a channel wall located opposite the opposite surface in thecircumferential direction.
 15. A clamping device in accordance withclaim 1, wherein a pin, via which the at least one clamping body issupported on the support surface, projects from the at least oneclamping body.
 16. A clamping device in accordance with claim 15,wherein the pin connects the at least one clamping body with at leastone said additional clamping body to form a clamping body group, and theclamping bodies of the clamping body group are supported via the pintogether on the support surface.
 17. A clamping device in accordancewith claim 1, wherein the channel is provided for a plurality of saidpackings arranged axially next to each other, and no more than a singleclamping body is provided per packing.
 18. A clamping device inaccordance with claim 1, wherein a single clamping body is arranged inthe channel.
 19. A clamping device in accordance with claim 1, whereinthe center of gravity of the clamping body is movable in relation to themounting means at right angles to the force exerted by the pressingmeans.
 20. A clamping device in accordance with claim 1, wherein anopposite surface each is formed for the clamping body on a leading sideof the channel and on a trailing side of the channel relative to therotating cylinder.
 21. A clamping device in accordance with claim 20,wherein the clamping gap can be formed with one or the other of theopposite surfaces as desired depending on the direction of rotation ofthe cylinder.
 22. A clamping device in accordance with claim 21, whereinthe pressing means presses the clamping body simultaneously with thepressing force against the opposite surface formed on the leading sideof the channel and with a pressing force against the opposite surfaceformed on the trailing side of the channel, wherein a force exerted bythe pressing means on the clamping body forms a triangle of forces withthe clamping force and the pressing force.
 23. A clamping device inaccordance with claim 22, wherein the opposite surface formed on theleading side of the channel and the opposite surface formed on thetrailing side of the channel are shaped such and oriented such inrelation to a radial to the axis of rotation of the cylinder that the atleast one clamping body is pressed against both said opposite surfaceswith a, essentially equal force each.
 24. A clamping device inaccordance with claim 1, wherein a plurality of the clamping bodies arearranged at axially spaced locations from one another and that thepressing means has a plurality of said spring elements, which arearranged at axially spaced locations next to each other in the channelalong a common longitudinal axis of the clamping bodies and act on theclamping bodies to generate the clamping force.
 25. A clamping device inaccordance with claim 24, wherein the clamping bodies a are seated on aaxis or preferably shaft or are made in one piece by a shaft, and thatthe spring elements act on the shaft such that a uniform clamping forceis generated over the length of the shaft.
 26. A clamping device inaccordance with claim 1, wherein the recess, which is formed on thejacket surface of the cylinder, and at least one said filler insertedinto the recess form the channel and the limiting edges of the openingof the channel.
 27. A clamping device in accordance with claim 26,wherein the recess is a straight axial groove with preferably parallel,flat side walls, which point at an angle to a radial relative to theaxis of rotation of the cylinder, and one of which forms the oppositesurface or another said opposite surface for the at least one clampingbody.
 28. A clamping device in accordance with claim 26, wherein thefiller has an inner edge, which is open toward two longitudinal sides ofthe filler, and in which it forms the opposite surface or another saidopposite surface for the at least one clamping body, the inner edgebeing preferably formed between two flat surfaces of the filler, whichpoint at right angles toward each other.
 29. A clamping device inaccordance with claim 1, wherein the channel widens in its cross sectionfrom the channel opening on both sides of the channel opening, so thatthe channel opening is formed between two said limiting edges which hasan acute-angled cross section.
 30. A clamping device in accordance withclaim 1, wherein the clamping body performs a rotary movement in aclamping direction of rotation when the flexible packing is pulled orpushed into the clamping gap, and that a blocking means is provided,which is coupled with the cylinder and with the clamping body andprevents a rotary movement of the clamping body against the clampingdirection of rotation in a releasable blocking engagement.
 31. Aclamping device in accordance with claim 30, wherein the blocking meansis formed by a friction brake or a free-running mechanism blocking theclamping direction of rotation.
 32. A clamping device in accordance withclaim 1, wherein the clamping body is rotatingly driven.